Configuration of Testcontainer, WebApplicationFactory and ConfigurationSource in ASP.NET Core.

// Program.cs
builder.Services.AddOptions<PostgreSqlConnectionOptions>().BindConfiguration("PostgreSqlConnectionOptions");
builder.Services.AddOptions<RabbitMqConnectionOptions>().BindConfiguration("RabbitMqConnectionOptions");

// PostgreSqlConnectionOptions.cs
public class PostgreSqlConnectionOptions
{
    public required string Host { get; set; } = "localhost";
    public required string Database { get; set; } = "myDb";
    public required string Username { get; set; } = "username";
    public required string Password { get; set; } = "password";
    public required int Port { get; set; } = 5432;
}